(CNN) - They may have their sights set on the White House, but Saturday they were in Sin City, talking up donation high rollers.

Several GOP leaders spoke at the Republican Jewish Coalition's annual spring leadership meeting in Las Vegas, where some of the party's most influential donors and fundraisers meet to talk politics and policy.

(CNN) – Former Florida Governor Jeb Bush spoke about foreign policy and the economic importance of immigration reform to a group of some of the most prominent Republican fund-raisers Thursday evening in Las Vegas, several attendees told CNN. Bush addressed a private, VIP dinner of major supporters of the Republican Jewish Coalition kicking off the group's spring meeting.

"He was passionate on the economic importance of immigration reform," an attendee told CNN. Bush has repeatedly pushed for action on immigration in the last couple of years.

Breaking Thursday morning: The Washington Post’s Robert Costa reports that Sen. Rand Paul of Kentucky has expanded his political network to all 50 states in an effort to broaden his base and lay the groundwork for a presidential campaign.

Costa joined CNN's "Inside Politics" to discuss his report that Paul’s nationwide team of 200 people blends traditional Republicans with the more libertarian-minded supporters of Paul’s father, Ron, who ran for president in 2008 and 2012.

Rand Paul’s challenge as a Republican, like his father’s, is to convince the national party that his views work with theirs. He opposes the war on drugs, for instance. He also opposes the use of drones to combat terrorism and the National Security Agency’s ability to collect phone and Internet data. Those are issues that draw support from national security hawks who have dominated the GOP for years.